Molded casket shell and trim therefore

ABSTRACT

A method of forming an article of manufacture which includes an undercut therein comprises the steps of providing a tool, removably positioning at least one consumable form adjacent to the tool, providing settable material from which to mold a finished part, molding the material onto the tool and on the form so as to encapsulate the form within the material to thereby form an undercut therein, allowing the material to set to form the finished part and separating the tool from the finished part and the encapsulated form. A method is also provided for forming articles of manufacture of various configurations utilizing a single generic tool by repeating the steps with differently shaped forms removably affixed to the single generic tool in different locations to produce a plurality of finished parts of varying configurations with the single generic tool.

This Application is a Division of Ser. No. 08/456,813 filed Jun. 1, 1995now U.S. Pat. No. 5,928,599.

FIELD OF THE INVENTION

This invention relates generally to the production of molded articles ofmanufacture, and more particularly to the production of molded plasticor composite articles of manufacture.

BACKGROUND OF THE INVENTION

Traditional methods of molding parts, for example plastic or compositeparts, by vacuum molding, sheet compound molding, reaction injectionmolding, injection molding and/or rotational molding have heretoforerequired an expensive, complex and specific tool with which to form aparticular molded part shape. Thus, should a plurality of shapes ofmolded parts be desired or required, a separate, specific tool isrequired to fabricate each specifically shaped part, thus substantiallyincreasing the costs to manufacturers.

Further, should a manufacturer desire to include features such asundercuts in a molded part, expensive, complicated collapsible toolingis required to remove the tool from the molded part in the area of theundercut. Such expensive, complicated tooling generally must include acomplex system of slides and ways to accomplish such collapsing toremove the tool from the formed part. Thus, manufacturers have eitherhad to purchase or construct such complex tooling in order to formundercuts in their molded parts, or have simply had to forego suchundercuts and in the process do without the substantial functional andaesthetic benefits and attributes attributable to such undercuts.

It is therefore one objective of the present invention to provide amethod of forming an article of manufacture including undercuts thereinwhich does not require the use of expensive, complicated collapsibletooling to accomplish the formation of the undercuts in the part.

It is another objective of the present invention to provide a method offorming articles of manufacture of various configurations utilizing onlya single generic tool rather than a plurality of specific toolsfabricated for each specific part configuration.

SUMMARY OF THE INVENTION

The present invention attains the stated objectives by providing amethod of forming an article of manufacture including an undercuttherein. The method comprises providing a tool, removably positioning atleast one consumable form adjacent to the tool, providing settablematerial from which to mold a finished part, molding the material on thetool including on the form so as to encapsulate the form within themolded material to thereby form an undercut therein, allowing the moldedmaterial to set to form the finished part, and separating the tool fromthe finished part and the encapsulated form.

The settable material may be plastic. The plastic material may be apreformed blank in the form of a sheet or tub. The sheet or tub may bevacuum molded onto the tool and form. The finished part may be a casketor many other articles of manufacture.

According to another aspect of the present invention, the form includesfasteners premounted thereon whereby cooperating hardware may beattached to the form fasteners after molding the plastic material ontothe tool and form. In the case of caskets, the premounted form fastenersor hardware may be used to attach casket handling hardware. Thepremounted form fasteners could be used for a variety of other purposesfor example as attachment sites for additional components, containers,electrical or fluid connectors etc.

According to yet another aspect of the present invention, the form iscolored and/or textured and the material is translucent whereby thecolor and/or texture of the form is visible through the translucentmaterial.

In still another aspect of the present invention, a method of formingarticles of manufacture of various configurations utilizing a singlegeneric tool is provided. The method comprises the steps of providing asingle generic tool, removably positioning at least one consumable formadjacent to the tool, providing settable material from which to mold afinished part, molding the material on the tool including on the form soas to encapsulate the form within the molded material to thereby definea specific configuration for the finished part, allowing the moldedmaterial to set to form the finished part, separating the tool from thefinished part and the encapsulated form, and repeating the above stepswith differently shaped forms removably affixed to the single generictool in different locations to produce a plurality of finished parts ofvarying configurations with the single generic tool.

One advantage of the present invention is that a method of forming anarticle of manufacture is provided wherein undercuts may be readilyincluded in the shape of the finished part, yet without having to employthe use of expensive, complicated and complex collapsible tools whichincorporate slides and ways.

Another advantage of the present invention is that a method of formingarticles of manufacture of various shapes with a single generic tool isprovided thereby obviating the need to have a specific, custom toolmanufactured to produce each differently shaped finished part.

These and other objects and advantages of the present invention willbecome more readily apparent during the following detailed descriptiontaken in conjunction with the drawings herein, in which:

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a fragmentary perspective view of a generic tool includingconsumable forms thereon utilized in the fabrication of an article ofmanufacture according to the principles of the present invention;

FIG. 2 is a cross-sectional view of the tool and forms of FIG. 1inserted into a preformed plastic tub blank;

FIG. 3 is a view similar to FIG. 2 illustrating the plastic tub beingheated and vacuum molded to the tool and forms during heating of theblank;

FIG. 4 is a view similar to FIGS. 2 and 3 illustrating the tool beingremoved from the finished molded part and from the encapsulated forms;

FIG. 5 is a view similar to FIGS. 2-4 of the finished part withencapsulated forms;

FIG. 6 is a view similar to FIG. 2 but of a different process forcarrying out the invention wherein the tool is inverted and a preformedplastic sheet blank is positioned above the tool and is heated to besubsequently drawn down over the tool;

FIG. 7 is a view similar to FIG. 6 illustrating the sheet drawn downover the tool;

FIG. 8 is a view similar to FIGS. 6 and 7 illustrating the sheet beingvacuum molded to the tool and forms; and

FIG. 9 is a view of the finished part with encapsulated forms removedfrom the tool.

DETAILED DESCRIPTION OF THE INVENTION

Referring first to FIG. 1, there is illustrated a generic tool 10utilized in forming an article of manufacture according to theprinciples of the present invention. The generic tool 10 as illustratedis generally rectangular in shape and may be sized appropriatelydepending on the specific part to be fabricated. Other shapes may beutilized for other applications. For example, one specific applicationof the present invention is in the fabrication of caskets; tool 10 wouldthus be sized accordingly.

The generic tool 10 includes a pair of end walls, one of which is shownat 12, and a pair of side walls, one of which is shown at 14. The toolmay also include a top wall 16 which may form a part of a “vacuum box”and a bottom wall (not shown). The side and end walls 12 and 14 includea-plurality of holes 20 which are in fluid communication with an outlet22 which is to be connected to a vacuum source for vacuum molding a parton the tool 10. While tool 10 is illustrated as being a male tool forforming thereon a female part, it will be appreciated that theprinciples of the present invention could as well be employed with afemale tool in the production of a male part, for example bath tubs,spas etc.

A plurality of forms 30 are removably positioned adjacent to the sideand end walls 12 and 14 of the tool 10. The forms 30 may have anyparticular cross sectional configuration which is desired, andpreferably are fabricated from inexpensive, light weight and stiffmaterial such as structural foam, wood, plastic extrusions or the like.The forms 30 may be removably secured to the side and end walls 12 and14 of the tool 10 by such means as low shear strength adhesives,double-sided tape, magnetics, a separate vacuum box, cylinders, pins orthe like. Alternatively, a free standing system could be employed forpositioning the forms adjacent the tool.

Referring now to FIG. 2, a preformed blank 40 of a settable material,for example plastic, which, as illustrated, is a generallyrectangular-shaped tub, may be supported in a fixture 42. The tool 10with forms 30 thereon is inserted into the blank 40 as is illustrated.

Referring now to FIG. 3, heat is applied from a heat source to the wallsof the tub 40 to soften the plastic, while at the same time the vacuumsource applies a vacuum to the tool 10 and through holes 20 thus vacuumforming or molding the softened plastic tub blank 40 to the side and endwalls 12 and 14 and bottom of the tool 10 and at the same timeencapsulating the consumable forms 30.

Once the plastic is allowed to cool and sets up, the tool 10 may beremoved from the finished part by simply pulling the tool out of thepart as is shown in FIG. 4. The tool simply shears away from the forms30 which have been encapsulated, or otherwise consumed, in the finishedplastic part.

A preferable material from which to form the preformed blank, and hencethe final part, as mentioned above, may be plastic, but other settablematerials which are at one point soft and subsequently harden or set upmay also be employed. Further, while vacuum molding may be the preferredmethod of molding the part, other methods of molding or forming may alsobe utilized in the practice of the present invention, for example suchas injection molding, rotational molding, sheet compound molding,reaction injection molding and pressure forming. Preformed blank shapesother than the preformed tub illustrated may be utilized such as simplesheets etc.

One particular product which lends itself to fabrication from thepresent invention as is mentioned above is a plastic casket, though manyother articles of manufacture may be fabricated according to theprinciples of the present invention, such as, for example, automotivebody panels, bathroom tubs and shower stalls, hot tubs, swimming pools,casket vaults, boats and the like, the invention therefore not beinglimited to the production of caskets.

An alternative method of attaching forms to the tool is to invert thetool and place a form having a generally L-shaped configuration on thetool edge formed by the tool side and bottom walls and the tool end andbottom walls, whereby the form is held in place on the tool simply bygravity.

In the production of caskets, the forms 30 may include premountedtherein fasteners whereby casket handling hardware may be attached tothe form fasteners after molding the plastic blank onto the tool andform. For example, a plurality of nuts could be pressed or otherwisemounted in the forms, and once the plastic casket is formed, one wouldneed only to pierce the plastic casket skin over the nut for threadablyengaging the nut with, for example, a threaded bolt to secure caskethandling hardware to the casket exterior. Other applications for otherproducts include providing attachment sites for additional components,electrical and/or fluid connections and the like.

The forms 30 also readily lend themselves to being brightly colored,which, when utilized with a translucent or transparent plastic to formthe casket, will be visible through to the exterior of the casketthereby providing a decorative, ornamental appearance. In addition, theforms 30 could be textured whereby the texture of the form would printthrough or otherwise be visible through the plastic. The colored and/ortextured forms could be utilized in the production of other articles ofmanufacture other than caskets as well.

A further advantage of fabricating articles of manufacture according tothe principles of the present invention is that the invention readilyprovides for the inclusion of a skeletal structural framework within thearticle thereby providing for additional stiffness and strength of thearticle and consequent ability to reduce the skin thickness of theplastic. The forms could be solid or hollow. If hollow, the forms couldbe filled with structural foam providing contiguous or continuous formsthereby unitizing the forms and improving the strength characteristics.The filling of the forms with structural foam can be accomplished withan injection orifice contained within the tool.

The method of the present invention also readily lends itself to theformation of articles of manufacture of various configurations bututilizing only a single generic tool. In this aspect, a first article ofmanufacture is fabricated according to the above-described steps inreference to the Figures. Then, those same steps can be repeated, butwith differently shaped forms removably affixed to the single generictool in different locations thereby to produce a plurality of finishedparts of varying configurations with the single generic tool.

Referring now to FIGS. 6-9, there is illustrated a preferred techniquefor vacuum molding an article of manufacture according to the presentinvention. In FIG. 6, tool 100 is inverted and has a bottom 102, sides104 and a top or vacuum box 106 connectable to a source of vacuum. Arectangular frame 110 clamps and supports a rectangular sheet of plastic112 around its periphery. Heat is applied to the sheet 112 from a sourceof heat 113 to soften the sheet 112. A form 114 which is generallyL-shaped in cross-section has a leg 116 and a foot 118. Foot 118 issupported atop the bottom 102 of the tool 100. As tool 100 is inverted,the casket or other article of manufacture fabricated by vacuum moldingsheet 112 to tool 100 will have the forms 114 associated with the bottomedge of the article of manufacture. Another form 120 includes anaperture 122 therein which accepts the foot 124 of an L-shaped bracket126 which is attached to tool 100. L-shaped bracket 126 may be fixed totool 100 or may be removably attached and adjustably repositionablerelative thereto as with the use of pins or other means of attachment tovary the position of form 120 relative to form 114.

As illustrated in FIG. 7, as rectangular frame 110 is drawn downwardlyover the tool 100, sheet 112 assumes the general rectangularconfiguration of the tool 100. As shown in FIG. 8, when vacuum isapplied from the source of vacuum 128, the sheet 112 closely conforms tothe tool 100 and the forms 114 and 120. As shown in FIG. 9, once theplastic sheet has been allowed to cool and set to form the plasticcasket, the casket is removed from the tool 100 and the frame 110 isremoved from the finished part.

Those skilled in the art will readily recognize numerous adaptations andmodifications which can be made to the present invention which willresult in an improved method of forming articles of manufacture, yet allof which will fall within the spirit and scope of the present inventionas defined in the following claims. For example the settable plasticmaterial would not have to be preformed into a sheet or tub blank aswhen utilizing the invention in conjunction with an injection moldingtechnique. Accordingly, the invention is to be limited only by the scopeof the following claims and their equivalents.

What is claimed is:
 1. A casket shell comprising: a single layer ofsettable material molded into the size and shape of a casket shell; aform positioned relative to said settable material only in an areaassociated with casket shell trim; said molded material being molded onsaid form so as to shape said material around said form thereby formingan undercut in said material, said form creating the appearance ofcasket shell trim; wherein said form is colored and said material istranslucent whereby the color of said form is visible through saidtranslucent material.
 2. A casket shell comprising: a single layer ofsettable material molded into the size and shape of a casket shell; aform positioned relative to said settable material only in an areaassociated with casket shell trim; said molded material being molded onsaid form so as to shape said material around said form thereby formingan undercut in said material, said form creating the appearance ofcasket shell trim; wherein said form is textured whereby the texture ofsaid form is visible through said material.
 3. A casket shellcomprising: settable material molded into the size and shape of a casketshell; said molded material being molded on a form so as to capture saidform within said material; wherein said form is colored and saidmaterial is translucent whereby the color of said form is visiblethrough said translucent material.
 4. A casket shell comprising:settable material molded into the size and shape of a casket shell; saidmolded material being molded on a form so as to capture said form withinsaid material; wherein said form is textured whereby the texture of saidform is visible through said material.
 5. A casket shell comprising:settable material molded into the size and shape of a casket shell; saidmolded material being molded on a form so as to capture said form withinsaid material; wherein said form is hollow and is injected withstructural foam thereby creating a unitized form structure about theperiphery of said casket shell.
 6. A casket shell comprising: settablematerial molded into the size and shape of a casket shell; a formpositioned relative to said settable material only in an area associatedwith casket shell trim; said molded material being molded on said formso as to shape said material around said form thereby creating aperipheral skeletal structural framework in said material and theappearance of casket shell trim.
 7. The casket shell of claim 6 whereinthe settable material is plastic.
 8. The casket shell of claim 6 whereinthe settable material is a composite.
 9. The casket shell of claim 6wherein said form includes fastners premounted thereon whereby hardwaremay be attached to said form after molding said material onto said form.10. The casket shell of claim 6 wherein said form is colored and saidmaterial is translucent whereby the color of said form is visiblethrough said translucent material.
 11. The casket shell of claim 6wherein said form is textured whereby the texture of said form isvisible through said material.
 12. The casket shell of claim 6 whereinsaid form is hollow and is injected with structural foam therebycreating a unitized form structure about the periphery of said casketshell.